The present invention relates to a coaxial connector contact that is used in electronic devices such as information terminal devices and computer-related devices as well as to a coaxial connector having such a contact.
A coaxial cable used in electronic devices such as information terminal devices and computer-related devices has a sheath, a shield conductor, an insulator, and a center conductor that are arranged in this order from outside. The shield conductor that is given a ground potential is provided around the center conductor for transmission of a data signal. Therefore, usually, a coaxial cable is provided, at one end, with a connector so that the center conductor and the shield conductor can easily be connected to the signal side and the ground side, respectively, of an electronic circuit board.
To attach a connector to one end of a coaxial cable, the coaxial cable is cut in such a manner that the center conductor, the insulator, and the shield conductor are exposed. Then, the center conductor of the coaxial cable is soldered to a flat bonding portion of a coaxial connector contact while being kept in contact with the latter. At this time, if the exposed portion of the center conductor is deviated from a prescribed position relative to the bonding portion, solder flows out of the bonding portion to lower the quality. In view of this, conventionally, various measures are taken in coaxial cable contacts to make it possible to keep the exposed portion of the center conductor in contact with the bonding portion in such a manner that the exposed portion of the center conductor is correctly located at the prescribed position relative to the bonding portion.
For example, JP-A-2001-43939 discloses a coaxial connector contact in which walls are formed adjacent to the front end and the rear end, respectively, of a bonding portion in the axial direction of the center conductor and the rear-end wall is formed with an insertion hole into which to insert the exposed portion of the center conductor. With this structure, the exposed portion of the center conductor of a coaxial cable can be positioned by inserting the exposed portion into the insertion hole of the wall and then bringing the end face of the insulator into contact with the wall. Further, since the two walls serve to prevent a solder outflow during soldering, the solder outflow can be prevented more reliably.
However, in the above conventional structure in which the exposed portion of the center conductor is supported by the rear-end wall in both of the front-rear direction and the right-left direction, the exposed portion of the center conductor is supported at one point on the proximal side. This results in a problem that the front end portion of the center conductor tends to deviate to a large extent from the prescribed position. To position the whole exposed portion of the center conductor at the prescribed position, it is necessary to carefully perform the work of bringing the exposed portion of the center conductor in contact with the bonding portion. This leads to problems of low productivity and increase in production cost, the latter being due to the necessity of a dedicated device for highly accurate positioning. These problems are particularly serious in miniaturizing a coaxial connector to decrease the size and thickness of an electronic device.
An object of the present invention is therefore to provide a coaxial connector contact that makes it possible to correctly bring the exposed portion of the center conductor into contact with the bonding portion at a prescribed position relative to the bonding portion and to easily perform the work of positioning the exposed portion of the center conductor at the prescribed position relative to the bonding portion without the need for using a special external device, as well as a coaxial connector having such a contact.
A coaxial connector contact according to a first aspect of the invention comprises a bonding portion to which an exposed portion of a center conductor of a coaxial cable is to be soldered while being in contact with the bonding portion; and positioning portions provided so as to be able to support the exposed portion of the center conductor at a plurality of positions in an axial direction of the center conductor so as to position the exposed portion of the center conductor at a prescribed position relative to the bonding portion.
In the above-configured coaxial connector contact, when the exposed portion of the center conductor of a coaxial cable touches the bonding portion, the positioning portions can support the exposed portion of the center conductor at a plurality of locations along the exposed portion and hence can position the exposed portion of the center conductor at the prescribed position. As a result, the degree of uniformity of positions of the exposed portions of center conductors of products can be increased and hence the variation in product quality can also be reduced. Quality deterioration due to a solder outflow from the bonding portion during soldering of the center conductor can be prevented. Further, since the exposed portion of the center conductor can be positioned at the prescribed position by the positioning portion when it touches the bonding portion, the work of positioning the exposed portion of the center conductor at the prescribed position can be performed easily without the need for using a special external device.
At least the positioning portion closest to the front end of the center conductor may have two support pieces that are formed so as to be able to support the side faces of the exposed portion of the center conductor from both sides.
With this structure, the position of the front end portion of the center conductor which is most prone to deviate from the prescribed position relative to the bonding portion can be restricted in the right-left direction between the support pieces. Therefore, the positioning in the right-left direction by the positioning portions can be performed with higher accuracy.
The two support pieces may be formed by cutting and erecting portions of the positioning portion so that they are located on both sides of the exposed portion of the center conductor and opposed to each other.
With this structure, since the support pieces extend over a long distance in the axial direction of the center conductor, the exposed portion of the center conductor can be positioned reliably between the support pieces even if the length of the exposed portion has some error.
The two support pieces may be formed by cutting and erecting, perpendicularly to the axial direction of the center conductor, portions of the positioning portion.
With this structure, since the support pieces extend over a long distance beside a mounting portion of the positioning portion, solder is not prone to leak from the positioning portion during soldering of the center conductor.
The interval between the two support pieces may decrease as the position goes upward.
With this structure, the positioning portion can position, with high accuracy, the exposed portion of the center conductor in both of the right-left direction and the top-bottom direction.
The interval between the two support pieces may increase as the position goes upward.
With this structure, even if the front end portion of the center conductor deviates from the prescribed position relative to the bonding portion when the exposed portion of the center conductor is set from above, the two support pieces guide the front end portion of the center conductor to the prescribed position. Therefore, the work of setting the exposed portion of the center conductor on the bonding portion can further be facilitated.
At least the positioning portion closest to the front end of the center conductor may have a support piece that is formed by cutting and erecting, perpendicularly to the axial direction of the center conductor, a portion of the positioning portion and that is formed with an insertion hole into which to insert the exposed portion of the center conductor.
With this structure, since the support piece extends over a long distance beside a mounting portion of the positioning portion, solder is not prone to leak from the positioning portion during soldering of the center conductor. Further, the positioning portion can position, with high accuracy, the exposed portion of the center conductor in both of the right-left direction and the top-bottom direction.
At least the positioning portion closest to the front end of the center conductor may have a support piece that is formed by cutting and erecting, perpendicularly to an axial direction of the center conductor, a portion of the positioning portion and that is formed with a recess in which to place the exposed portion of the center conductor.
With this structure, since the support piece extends over a long distance beside a mounting portion of the positioning portion, solder is not prone to leak from the positioning portion during soldering of the center conductor. Further, the work of setting the exposed portion of the center conductor on the bonding portion can be facilitated because the exposed portion of the center conductor can be set in the recess from over the positioning portion.
A coaxial connector contact according to a second aspect of the invention comprises a bonding portion to which an exposed portion of a center conductor of a coaxial cable is to be bonded with solder while being in contact with the bonding portion at a prescribed position; a first positioning portion that is provided at a position to be located on a front side of the exposed portion of the center conductor and is formed so as to be able to support side faces of the exposed portion of the center conductor from both sides; and a second positioning portion that is provided at a position to be located on a proximal side of the exposed portion of the center conductor and is formed so as to be able to support side faces of the exposed portion of the center conductor from both sides and to be in contact with an end face of an insulator that covers the center conductor.
In the above-configured coaxial connector contact, when the exposed portion of the center conductor of a coaxial cable touches the bonding portion, the positions, in the right-left direction, of the front end portion and the proximal portion of the exposed portion of the center conductor are restricted by the first positioning portion and the second positioning portion, respectively, whereby the whole exposed portion of the center conductor can be positioned with high accuracy at the prescribed position relative to the bonding portion. Since the second positioning portion is in contact with the end face of the insulator, the exposed portion of the center conductor can be positioned correctly in the front-rear direction, that is, in its axial direction. As a result, the variation of the position of the exposed portion of the center conductor among products can be reduced. And quality deterioration due to a solder outflow from the bonding portion during soldering of the center conductor can also be reduced. Further, the work of positioning the exposed portion of the center conductor at the prescribed position can be performed easily without the need for using a special external device.
The second positioning portion may have a guide groove whose width increases as the position goes upward and that guides the exposed portion of the center conductor to the prescribed position.
With this structure, even if the proximal portion of the exposed portion of the center conductor deviates from the prescribed position relative to the bonding portion when the exposed portion of the center conductor is set from above, the guide groove guides the proximal portion of the exposed portion of the center conductor to the prescribed position. Therefore, the work of setting the exposed portion of the center conductor on the bonding portion can further be facilitated.
A coaxial connector according to the invention comprises a coaxial connector contact having at least one of the above-described features.
The coaxial connector having such a structure can be produced at a high yield.